Bernie Sanders showed in 2016 that an unabashed liberal with a fervent following could reach the cusp of the Democratic nomination. Now a slew of progressive Democrats are following his lead.

More than two years before the next presidential primaries, roughly a dozen potential candidates pushing liberal economic agendas are making initial moves in preparation for a run. Sanders himself has visited early-voting states. Fellow senators including Elizabeth Warren of Massachusetts and Jeff Merkley of Oregon have been meeting with activists. And governors such as Montana’s Steve Bullock are hiring political teams. Even a handful of mayors have started getting into the action.

Indeed, the lion’s share of activity among potential 2020 hopefuls so far is on the progressive end of the Democratic spectrum — an indication of a broader ideological swing in a party struggling to be seen as more populist.

The maneuvers shed light not only on the contours of Democrats’ aggressive march toward 2020, but also how fundamentally Sanders’ 2016 bid reshaped ambitious pols’ views of what arguments break through in the age of President Donald Trump.

“Of the names being talked about — [California Sen. Kamala] Harris, [Los Angeles Mayor Eric] Garcetti, [Connecticut Sen. Chris] Murphy, [New York Sen. Kirsten] Gillibrand, and a long list of others — almost all have staked out positions on Medicare-for-all, immigration and the economy which are more progressive than any Democratic nominee since 1972,” said Howard Dean, a former Vermont governor and Democratic National Committee chairman who ran for president as a liberal insurgent in 2004.

“It’s about damn time,” added retired Iowa Sen. Tom Harkin, the liberal stalwart who ran for president in 1992.

Across the country, Democratic pols have flocked to embrace many of the policy proposals that animated Sanders’ 2016 campaign, from increasing the minimum wage to lightening college debt loads. And in the Senate, the health care debate has revealed a similar dynamic: potential 2020 hopefuls Harris, Warren, Merkley, Gillibrand and New Jersey Sen. Cory Booker have announced they will co-sponsor their Vermont colleague’s Medicare-for-all bill, and Murphy has proposed an alternative to a single-payer system while praising Sanders.

Sanders still looms large enough that for Democrats considering presidential runs, the first question they must consider is how a potential Sanders bid would affect their own campaign, said multiple leading Democratic operatives. The Vermont independent has refused to rule out a 2020 run and has made political waves by visiting early voting states Iowa and New Hampshire repeatedly this summer.

Sanders — who remains in touch with Harkin, and whose top two 2016 Iowa operatives are back in the state — has also made political trips to battleground states including Ohio, Pennsylvania and Michigan.

But his presence hasn’t stopped other potential presidential hopefuls from moving toward running, even as they are quick to give him partial credit for forcing the party to move left.

The primary electorate’s expectations have started moving as well, according to party officials in influential states.

“It’s migrating that way due to the influence of Bernie Sanders and the impact he had of drawing in that group of people,” said Linn County, Iowa, Democratic Party Chairman Bret Nilles. “That wing of the party is starting to become more vocal and more engaged.”

Aside from Sanders, Warren is the most prominent potential progressive contender, much as in the run-up to 2016, when pieces of the apparatus dedicated to drafting her turned into the basis for Sanders’ campaign. She is holding donor meetings, having sit-downs with influential activists and making speeches to liberal groups like those gathered at last month’s Netroots Nation conference. In the run-up to her 2018 reelection and possible 2020 bid, she has also brought on new digital staffers in a likely prelude to a grass-roots fundraising and organizing campaign like the one Sanders ran nationwide.

Sanders’ lone Senate endorser in 2016, Merkley is also taking far more advanced steps toward a potential bid than is widely recognized.

For months, Merkley has been convening liberal outside groups in his Senate office every two weeks to help guide the messaging and tactics of the Trump opposition. Beginning as an effort to talk about pressuring a President Hillary Clinton on Cabinet picks, Merkley’s meetings have turned into convening points for senators including Warren, Sanders, Harris, Murphy, Booker and other possible 2020 hopefuls like Ohio’s Sherrod Brown, in addition to Hawaii’s Brian Schatz.

Merkley is also increasing his presence in early voting states. After placing an op-ed in The Des Moines Register just before Labor Day — praising Iowa’s “long, proud populist tradition” and noting its “outsized role in national politics” — the second-term senator swung through Iowa’s capital over the weekend for an event hosted by the Progress Iowa group and town hall-style meetings with students at Harkin’s institute at Drake University.

Merkley — who, like Sanders, keeps in touch with Harkin — also scheduled roughly half a dozen private weekend meetings with local donors and liberal activists who are central to the nominating process.

But with Democrats viewing Trump as vulnerable, and upstart progressives feeding off grass-roots energy, the list of potential left-leaning contenders goes far beyond the traditional Senate and gubernatorial routes.

“There’s a big reset happening in the Democratic Party right now, so you might as well get out there,” said Sean Bagniewski, chairman of Iowa’s Polk County Democratic Party. “People who are calling Iowa have three traits: They’re a new face in some ways, they’re bolder in their message — they know we’re not going to beat Trump by being Trump, but times are drastic — and there’s a much more economic focus than ever before.”

Former Missouri Secretary of State Jason Kander, for one, has told donors he sees room for a possible nationwide run within Sanders’ political lane. After falling short with a 2016 Senate bid, Kander launched a voting rights group and quickly became a mainstay in the state Democratic Party speaking circuit. He’s made multiple visits to both New Hampshire — which he quietly visited last week to have drinks with the board of the Young Democrats group — and Iowa.

Activists immediately ascribed presidential intentions to his group’s move last month to open field offices in Iowa, New Hampshire and fellow early-voting state Nevada, dispatching his former campaign manager to run the show in Iowa.

And Garcetti, who visited New Hampshire last month, isn’t the only mayor making moves.

New York City Mayor Bill de Blasio has talked to political allies and donors about carving out a broader national stature after what’s expected to be a wide reelection victory later this year, pitching the idea of doing a speaking tour all over the country.

Even Pete Buttigieg — the 35-year-old mayor of South Bend, Indiana, who this year ran unsuccessfully to lead the Democratic National Committee — is taking a run at it, with four events in central Iowa over the weekend.

“We’ll stand up to a president who cheapens the most respected office in our land with the heart of a miser, the mind of a cheater, and the soul of a schoolyard bully,” Buttigieg said there on Sunday.

Centrist Democrats have for months chafed at the notion that Sanders’ ideas and politics are ascendant within the party.

But so far before the voting process formally starts, the potential left-wing contenders have faced little blowback.

“For too long, liberals, progressives, whatever you want to call them, have been following the polls to a deleterious effect. They’re chasing poll numbers around,” said Harkin, embracing the shift.

“Politics is essentially winning the hearts and minds of people, and you can’t win the hearts and minds of people by telling them that you’ve lost yours, and could they please point you in the right direction. And that’s what we’ve been doing.”